Question

1. What happens to the blood pressures in the subject’s left leg when the subject reclines? When the subject lifts his or her left leg perpendicular to the bench? When the subject stands? After the subject has been standing for three minutes?

Answer 1

There will be no big difference in blood pressure in leg or any other part of the body,even when a person who has reclined his leg or whether it is perpendicular to bench or when after standing for 3 minutes.

As the body has enough compensation mechanisms to adapt varying posture.Blood pressure is more in legs than arms simply because of gravity,which is more in legs and blood has to be pumped against gravity. So this causes extra burden on Autonomic nervous system to clear blood from lower extremities. BP difference should not be greater than 10 mm of hg in lower limbs than upper limbs.

when a individual or subject stand up from lying down or sitting,a small momentary dip in BP occur s in first few seconds.This occurs because gravity causes about 0.5 to 1 litre of blood to pool in lower body.

Body normally corrects for this unnoticeable blood pressure dip rapidly usually in 30 seconds.

In reclining position,the hydrostatic pressure (pressure of a column of fluid) is minimized.

when patient stands,then there is hydrostatic effect.There is also some degrees of blood pooling in distensible leg veins.Hence,upper body blood pressure drops.

however,in young fit and healthy subjects there are a set of reflex mechanisms to adjust this.These reflexes include initiation of tachycardia which means increasing heart rate to increase blood pressure.

GOOD LUCK!!!